Page 21 - 38 rid

ARTICLE IN PRESS
50 L. Ferranti et al. / Quaternary International 145– 146 (2006) 30–54
eustatic reference (673 m) for the central Mediterra-
nean.
The Ligurian Sea coasts display different local uplifts
between the western (Alpine) and eastern (Apenninic)
sectors, mirroring its geologic history of vertical
displacement and testifying a still active separation
between the Alpine and Apenninic compartments. The
northern Adriatic coasts trend from weak uplift to
strong subsidence towards the north, and this probably
reflects the transition from imbrication in the shallow
thrust wedge to deep crustal flexure towards the
northern Apennines orogen (Figs. 5 and 13). Foreland
flexure beneath the northern Apennines is consistent
with the model of slab roll-back of the Adriatic
lithosphere explaining the rapid advancement of the
thrust belt (Royden et al., 1987; Doglioni, 1991). The
central and northern coasts of the eastern Tyrrhenian
Sea are generally stable (promontories) or slowly
subsiding (plains), and localized volcano-tectonic effects
are observed as mild uplift and moderate subsidence
within Lazio and Campania, respectively.
Overall, the central and northern Tyrrhenian and
Adriatic coasts pass from stability or weak uplift to
subsidence. The coasts run across the north-western part
of the Adriatic block, which is caught between the African
and European plates and is characterized by slower
geodetic motion and less seismic release than its south-
eastern counterpart (Fig. 14; Oldow et al., 2002; Oldow
and Ferranti, 2005). Thus, a relation ensues between
stability to subsidence and moderate deformation rates.
On the other hand, regional uplift characterizes the
southeastern Tyrrhenian, southern Adriatic and Jonian
coasts, which span the southeastern sector of the Adriatic
block (Fig. 14), where GPS velocities are faster and
seismicity is higher (Oldow et al., 2002; Oldow and
Ferranti, 2005). The uplift is weak in Puglia and in
western and southern Sicily, but increases towards the
canter of the block peaking between Sicily and Calabria,
and far to the northeast in the central Jonian coasts
(Fig. 14). The bulge might have a common origin and
span over a wider lithospheric area than the subducted
Ionian slab underneath the southern Tyrrhenian Sea
(Fig. 5a), which is traditionally claimed as the source for
Calabria’s uplift (Cosentino and Gliozzi, 1988; Westaway,
1993; Gvirtzman and Nur, 2001). Although the western
side of the bulge resides in an area of extensional
tectonics, a component of crustal or even lithospheric
shortening related to Adria–Europe interaction might
contribute to the uplift in the eastern sector.
7. Conclusions
The coasts of Italy display well-developed and well-
preserved indicators of the MIS 5.5 sea-level highstand,
which provide excellent information about altitude and
time. The distribution of the indicators reflects primary
paleoclimatic and paleogeographic conditions and sub-
sequent tectonic processes, manifested in a combination
of regional and local displacements. Compilation of
altitudes of 246 MIS 5.5 shoreline outcrops along the
coastline of Italy, supported by uncertainty estimation
of both age and elevation, provides an insightful picture
of the recent and active tectonic processes in the central
Mediterranean. The vertical displacement experienced
by the highstand marker is complicated at the local
scale, but in the regional frame appears consistent with
stability to slow subsidence in Sardinia and the central-
northern Tyrrhenian sea, slow to rapid uplift moving
north along the Adriatic coast, and rapid uplift of the
southern Tyrrhenian and Jonian coast. Viewed at this
scale, the along-shore variability in the marker elevation
highlights different tectonic processes in laterally ad-
joining compartments. Displacement of the marker is
thus a response to both surface and deep crustal
processes, and, in the absence of more recent indicators,
the MIS 5.5 highstand marker stands as an unsurpassed
proxy for the vertical component of active tectonic
displacement in the Central Mediterranean.
Acknowledgements
We thank journal reviewers S. Kershaw and Y. Ota
for insightful comments, which helped to clarify the
contents of this paper. Published thanks to financial
support of Project S2 2005/2006 ‘‘Valutazione del
potenziale sismogenetico e probabilita` dei forti terremoti
in Italia’’ by Istituto Nazionale di Geofisica e Vulcano-
logia – Dipartimento Protezione Civile – Unit S2.1.:1
(Resp Giuseppe Mastronuzzi), and by research grants
from Catania University (Resp. Carmelo Monaco).
Appendix A. Supplementary materials
Supplementary data associated with this article can
be found in the online version at doi:10.1016/
j.quaint.2005.07.009
References
Amato, A., 2000. Estimating Pleistocene tectonic uplift rates in the
South-Eastern Apennines (Italy) from erosional landsurfaces and
marine terraces. In: Slaymaker, O. (Ed.), Geomorphology, Human
Activity and Global Environmenral Change. Wiley, New York,
pp. 67– 87.
Amato, A., Montone, P., 1997. Present-day stress field and active
tectonics in southern peninsular Italy. Geophysical Journal
International 130, 519– 534.
Amorosi, A., Colalongo, M.L., Pasini, G., Preti, D., 1999a.
Sedimentary response to Late Quaternary sea-level changes in the
Romagna coastal plain (N. Italy). Sedimentology 46, 99– 121.